Conductor support



Aug. 15, 1944. R. P. HANNA 2,356,052

CONDUCTOR SUPPORT Filed July 15, 1941 f/y. 3. 40 40 I fi 'a4 46 4.4 47 45 g 49 5/ 55 =1 m m WITNESSES: INVENTOR Fay/Wand P fia/ma,

' TTORNEY Patented Aug. 15, 1944 UNITED STATES PATENT OFFICE CONDUCTOR SUPPORT Pennsylvania Application July 15, 1941, Serial No. 402,471

8 Claims.

My invention relates, generally, to conductor supports, and it has reference in particular to insulated supports for trolley conductors.

Generally stated, it is an object of my invention to provide an improved insulated trolley conductor support which will be simple and inexpensive to manufacture and which has increased protection against failure by fiashover.

More specifically, it is an object of my invention to provide for utilizing auxiliary arcing means with insulated trolley conductor supports so asto provide a predetermined gap between the conductor and ground away from the insulation of the support having a breakdown voltage less than the wet fiashover value of the insulation.

Another object of the invention is to increase the life of insulated trolley conductor hangers or supports by preventing flashover across the insulating material thereof.

A further objectof the invention is to provide a predetermined gap between the conductor and a metallic hood or cap on an insulated trolley conductor hanger so as to prevent arcing from the hood or cap across the surface of the insulating material. I

Yet another object of the invention is to providea detachable arcing device for use with insulated trolley conductor hangers which may be used with different types of trolley earsto provide a predetermined protective gap for the insulated hanger.

Other objects will in part be obvious, and will in part be described hereinafter.

v In accordance with my invention, the life of insulated hangers used in trolley conductor systems may be greatly increased by providing a protective gap between the conductor and a grounded portion of the hanger more or less remote from the insulation of the hanger. An arcing member may be positioned between the hanger and a trolley'ear supported therefrom, and secured in predetermined relation to a grounded portion of'the'hanger by means of" the trolley car. The'arcing member may, for exarnple, be provided. with upwardly projecting end portions positioned in predetermined relation to the metallic hood or cap of the insulator so as to provide a protective gap therebetween having abreakdown value of substantially less than the wet flashover value of the insulator and relatively remote from the insulating-material thereof.

For a more complete understanding of the nature and scopeof my invention, reference may be had to the accompanying drawing, in which: Figure 1 is a sideelevational view partly in sec-' tion of a trolley conductor support embodying the principal features of the invention,

Fig. 2 is an end elevational view of the conductor support of Fig. 1,

Fig. 3 is a plan view of the arcing member, and

Fig. 4 is a side elevational view of a trolley conductor support embodying a modification of the invention.

Referring to Figs. 1 and 2, the reference numeral l0 may denote, generally, an adjustable insulated hanger which may be attached to a support wire II for supporting atrolley ear I2 which is adapted to engage and support a trolley wire l3. An arcing member or device l4 may be utilized to provide a protective gap between the conductor and ground having a predetermined voltage breakdown value.

The hanger l0 may be of any suitable construction comprising, for example, a substantially cupshaped metallic cap or shell l5 having a support stud l6 secured therein in spaced and insulated relation by means of insulating material IT for supporting the trolley ear l2. A headed portion [8 may be provided on the upper surface of the cup or shell l5 connected thereto by a neck portion I!) of reduced cross section.

In order to secure the cap or shell l5 to the support Wire H and provide for relative motion therebetween, upper and lower clamp members 20 and 2| may be provided having cooperating grooves 22 and 23 therein for receiving the support wire ll. Means in the form of bolts 24 may be provided for adjustably connecting the clamp members together. The lower clamp member 2| may be provided with a socket portion 25 adapted to receive the headed portion l8 of the cap or shell l5 and a side opening 26 to receive the neck portion I9 so that when the bolts 24 are tightened, the support wire I l is securely clamped and the head portion I8 is locked relative to the clamp members 20 and 2|.

The trolley ear l2 may be of any suitable design comprising, for example, an elongated body member 26 having a central boss 21 for receiving a threaded portion of the stud I6 and depending lip portions 28 adjacent the ends provided with longitudinal grooves 29 adjacent the lower edges thereof to receive the upper portion of the trolley wire l3. Clamp members 30 having similar cooperating grooves 3'! may be attached to the body portion by means of bolts or hollow screw members 32 so as to securely clamp the upper portion of the trolley wire l3 in the grooves 29 and '31.

In order to protect the hanger ill from damage by a flashover resulting from an electrical disturbance in the trolley conductor system, the auxiliary arcing member l4 ma be positioned in predetermined relation to a grounded portion of the hanger, such as the cap or shell 15. The arcing device may, for example, comprise an arched central body portion 35 having an opening 35 therein for positioning the arcing member on the support stud l6. Depending ear portions 38 may be positioned in spaced relation adjacent the ends thereof adapted to engage the body portion 26 of the ear on opposite sides so as to maintain the body portion 35 of the arcing member in alignment with the body portion of the trolley ear. Adjacent each end of the body portion 35 upstanding arcing horns 40 may be provided. The arcing horns 40 may be inclined outwardly and provided with relatively sharp edge portions 4| on the inner edges thereof so as to provide a predetermined gap (a) between the cap or shell [5 and the horn 40 having a minimum spacing with a flashover value less than the wet flashover value of the insulation ll between the cap or shell l5 and the support stud l6 and a gradually increasing spacing thereabove.

For example, where the dry fiashover value between the cap or shell and support stud of a hanger may be 17 kv. and the wet flashover value of the same hanger may be 10 kv., I prefer to provide a minimum gap between the cap or shell and the arc horn having a breakdown voltage of approximately 8 kv. Thus when there is an electrical disturbance in the trolley conductor system causing a surge therein, any flashover between the trolley conductor and ground will take place across the gap (a) instead of across the surface of the insulator ll. The insulating value of the insulated hanger 10 may thus be maintained substantially constant over a long period of time even though there are numerous flashovers between the trolley conductor and ground caused by electrical disturbances in the trolley conductor system. Since these fiashovers occur across the protective gap provided between the arcing member and the shell of the insulated hanger where no harm can result, and they are easily extinguished by the upwardly increasing gap, the insulation ll does not become charred as heretofore when flashovers occurred across the insulation, and its electrical resistance is not reduced by such fiashovers.

Referring to Fig. 4, it will be seen that the insulated trolley hanger 44 may be of substantially the same construction as the insulated hanger of Figs. 1 and 2 having a cap or shell 45 with a stud 46 secured therein in insulated and spaced relation by insulation 41, but may be modified so as to provide sloping inner surface portion 48 about the lower edge of the cap or shell 45 to provide a relatively sharp outer edge portion 49 which results in a lower breakdown voltage for a given gap. The trolley ear 50 may be of a different type than that shown in Figs. 1 and 2, and may comprise an elongated body portion having a threaded central boss portion 52 and depending lip portions 53 adjacent the lower edge for engaging a trolley conductor 54. Means such as the projections 55 on the upper side of the body portion adjacent the edge portion 49 of the cap or shell may be so arranged as to provide predetermined gaps (b) between the sharp edge portion 49 of the cap or shell 45 and the body portion 5| of the trolley car having a breakdown value less than the wet breakdown value of the hanger 44 across the insulation 41 thereof, so

that any flashover will occur at the gaps (b) and not across the insulation.

From the above description and the accompanying drawing, it will be apparent that I have provided a simple and effectiv manner for protecting insulated trolley hangers against damage from fiashovers. B using an auxiliary arcing member secured in predetermined relation to a grounded portion of the insulated hanger by means of the trolley ear, a predetermined protective gap for the insulated hanger may be provided more or less remote from the insulation, which is independent of manufacturing variations in the trolley ear so that one form of arcing member may be used with numerous sizes and types of trolley ears to provide a uniform degree of protection for the hangers with which they are used.

Since certain changes may be made in the above description and different embodiments of the invention may be made without departing from the spirit thereof, it is intended that all the matter contained in the above description or shown in the accompanying drawing shall be considered illustrative and not in a limiting sense.

I claim as my invention:

1. A trolley conductor support comprising an insulated hanger having a relatively thick walled metallic cap having a relatively sharp edge on the outer side of the rim and provided with a support stud positioned therein in insulated relation by insulating material interposed therebetween to provide a predetermined creepage distance, a trolley ear detachably secured to the support stud and adapted to be secured to the trolley conductor, and an arc member supported by the trolley ear interposed between the trolley ear and the cap adjacent the relatively sharp edge to provide a substantially knife edge gap therebetween having a breakdown value less than the wet flashover value of the surface of the insulation between the stud and cap.

2. The combination in a trolley conductor support, of an insulated hanger having an inverted metallic shell with a bevelled rim portion providing a relatively sharp edge and a stud supported therein in insulated relation by interposed insulation, and a trolley ear detachably secured to said stud having upwardly projecting means integral with the ear positioned adjacent the relatively sharp edge of the shell to provide'a substantially knife edge gap remote from the insulation having a breakdown value substantially less than the wet surface flashover value of the insulation between the stud and the shell.

3. A trolley ear adapted to be supported by an insulated hanger having a metallic shell with a relatively sharp edge about the outer rim and provided with a support stud secured therein by insulation, comprising, an elongated body portion having depending lips to receive a trolley conductor, a boss for detachably securing the body portion to the hanger stud, and an upwardly extending arc member integral with the body member so positioned relative to said edge of the outer rim of the shell of the hanger as to provide a gap between the arc member and an outer portion of the shell spaced from the insulation having a fiashover value less than the wet flashover value of the hanger across the insulation.

4. A protective device for a trolley conductor support having a support stud secured in a metal shell by interposed insulation for securing a trolley device comprising, an arc member having an upwardly extending horn at one end positioned in predetermined spaced relation to and extending outside of an outer portion of the metal shell to provide an upwardly divergent gap and a portion positioned on the stud cooperative with the trolley device to secure the arc member in said predetermined relation.

5. The combination with a trolley ear supported by an insulated hanger having a support stud positioned in a shell by interposed insulation, of an arc device having a portion interposed between the ear and hanger and a portion extending upwardly and in predetermined spaced relation to the outer edge of the shell to provide a gap having a breakdown voltage less than the breakdown voltage of the hanger clear of the insulation thereof, and means associated with the portion between the ear and hanger cooperative with the ear to retain the upwardly extending portion in predetermined relation to the ear.

6. The combination with an elongated trolley ear and an insulated hanger having a metallic shell with insulation therein positioning a support stud therein in spaced and insulated relation for supporting the trolley ear, of a protective device having a body portion positioned about the stud between the ear and shell and extending in the longitudinal direction of the ear, an upwardly extending end portion extending adjacent the outer edge of the shell to provide a gap less than the surface distance between the stud and shell, and means on the body portion engaging the ear to aline it with the ear.

'7. An arc device for use with a metal sheathed insulated hanger and a trolley ear comprising, a body portion arranged to be positioned between the trolley ear and hanger having an opening therein for securing the device relative to the hanger and depending spaced projections on th lower side to one side of the opening operable to aline the arc device relative to the ear, and an upwardly projecting end arcing portion inclined outwardly from the body portion and arranged in arcing relation to the outer surface of the metal sheath of th hanger.

8. A protective device for an insulated hanger having a metallic shell with a support stud secured therein for supporting a trolley conductor support comprising, a central portion adapted to be secured between the support and the hanger, means on said portion to maintain said portion in alinement with the support, and end portions projecting upwardly from the central portion in predetermined spaced relation to the shell.

RAYMOND P. HANNA. 

